BRUSSELS (AP) — The European Union is praising Facebook, Google and Twitter for tackling disinformation while urging the social media giants to do more in clamping down on fake accounts.

Under an EU code of conduct, the three companies report routinely on their efforts to stop election interference. Facebook, for one, has been criticized for being a tool for foreign interference in elections.

Tuesday's reports say Facebook, Google and Twitter are tightening advertising policy and surveillance, particularly with election-targeted ads.

But the commission urges them to share fake account data with outside experts and researchers.

Millions of people across the 28-nation bloc will vote in the May 23-26 European Parliament elections.

Polls show nationalist and populist parties could make significant gains, while mainstream parties would lose seats but retain control over the assembly.